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The Earth's oceans are rising. It's an inevitable outcome when ice sitting on land melts and when oceans warm, which causes their volume to expand. But if you live at the coast, it may not be rising near you. Places like Miami and Newport News are experiencing floods at many high tides. Some places in Alaska, in contrast, are seeing the oceans edging away, as land seems to lift out of the sea (albeit incredibly gradually).

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It happens because the Earth's not a bathtub—adding more water doesn't increase ocean levels evenly. As this video details, there are lots of factors that add a local twist to the overall rise of the oceans. These factors range from the strength of ocean currents to the gravitational pull of large ice fields. The net result is that the US has some areas where ocean levels are actually falling a bit and many others where they're rising even faster than the global average.

While the effects are small, they can make a huge practical difference, determining whether your neighborhood is flooding now, or if you have decades to prepare for problems.

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

Edit: Not sure why I'm being downvoted. I was just generally curious why CO2 is almost always the only cause mentioned in climate change articles. I'm well aware of the wobble in the Earth's orbit as well as Milankovitch cycles. That PBS Space Time video "Is Another Ice Age Coming?" is extremely educational and points out other causes to our rising global temperatures. It also explains how the Earth went through phases of extremely hot and extremely cold climates and all the conditions that line up to put Earth into these scenarios as well as take Earth out of them. I appreciate all the answers I've gotten to my original question but again I'm aware of them. I just feel like CO2 should be mentioned AND THEN maybe one or two other causes. There were 2 eruptions in the 1800s that basically caused years without a summer. Who's to say that won't happen again and turn down the global temperature for a time? But trust me I'm all for ending CO2 emissions and having a healthier atmosphere for our future generations

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

Look at everything climate deniers say could be causing the change in the climate (that they also deny) -- the tilt of the Earth's axis, change in orbital eccentricity, and the like. The formal name is the Milankovitch Cycle, which is a legitimate scientific theory that has little to do with atmospheric CO2 (other than releasing any gas trapped in the glaciers, which is a positive feedback in the system, something else that deniers deny.)

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

Look at everything climate deniers say could be causing the change in the climate (that they also deny) -- the tilt of the Earth's axis, change in orbital eccentricity, and the like. The formal name is the Milankovitch Cycle, which is a legitimate scientific theory that has little to do with atmospheric CO2 (other than releasing any gas trapped in the glaciers, which is a positive feedback in the system, something else that deniers deny.)

And it's important to note that the previous climate change events occurred over geologic timescales, which is why the biosphere didn't go into crisis every time. All of the denier forcings do indeed drive climactic change...on geologic timescales. The only known forcing that could possibly work on human timescales is greenhouse gases. If someone wants to try modeling the current trends with the other forcings, it'd certainly be an interesting study to read.

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

To expound on what you're saying, its important to remember that the last ice age receded over what was maybe thousands of years. The speed at which the change is happening now is beyond natural cycles.

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

Short story: increasing inclination of Earth’s orbit means longer summer days near the poles — and also longer winter nights. There’s no direct effect on the average temperature. But, longer days in summer melts ice in summer, which means the surface of the ice gets dirty (or the ice melts down to rock and dirt). That dirt absorbs more sunlight as heat, and that leads to higher global temperatures.

In turn, that leads to warmer oceans. Warmer oceans can’t dissolve as much CO2, so now there’s more CO2 in the atmosphere — which leads to further warming.

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire?

The same thing that mostly caused the glaciers to form in the first place. Orbital wobbles that change how much sun we get in certain parts of the world, which changes the dynamics of the climate system to either encourage or discourage ice sheets from forming. There are a lot of complex feedbacks, but the first trigger is probably the periodic wobbles of the Earth in its orbit.

These days, the impact of our greenhouse gases is much stronger than the wobbles that caused the "ice ages."

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

And one of the most interesting tidal magnitude visualizations of Amphidromic points:

Also, the gravitational field produced by the mass on Earth is decidedly not smooth. Gravity differences based on local mass concentration will cause water to pile higher or lower depending on the local mass.

There seems to be some coloration between these two maps.

The question is, is the tide causing the gravity anomalies, or is the gravity causing the tidal anomalies?

Cool article - it's a much more complex subject than one might initially expect. I wonder if the gathering of water about the equator as the pole ice melts will cause a measurable decrease in the rate of the Earth's spin.

But can someone explain how the glaciers during the height of the last ice age retreated long before humans ever started putting CO2 into the atmosphere? Toronto was under an ice sheet over a mile thick. How did all that ice disappear when humans were just beginning to harness fire? I wish climate change articles would go into more detail about the causes and not always point the blame at CO2 emissions. Sure, that is definitely a main, if the THE main culprit, but there are many other factors at work that barely ever get mentioned

There are long term effects caused by the degrees of eccentricity in the Earth's orbit. This leads to long term trends of cooling then warming. However at the end of glacial periods you get climate ripples that in the northern hemisphere cause rapid temperature increases of between 10-18 degrees over 25 years or so, in the south it's 8-10 degrees. There hasn't been one since the last galcial period so what the actual cause of the ripples is unknown. To be utterly pedantic, hooray for the opportunity, we are still in an ice age because of the polar ice sheets. Technically we are in an intergalcial period